This invention relates to coupling means between a thermal motor shaft and a reciprocating pump shaft.
Thermal motors are known and widely available, they being typically intended to be coupled to electrical generators, the motor shaft of which has at its end a frusto-conical surface for coupling to that member of the generator which is to be rotated; coupling is achieved by axially forcing together the frustoconical surface of the shaft and a corresponding surface of the rotary member, in particular by means of a screw, the shank of which is engaged in an axial hole provided at the shaft end to axially force the rotary member against the shaft.
Reciprocating pumps are also known, particularly for water, their shaft presenting at the coupling end a cylindrical axial cavity adapted to receive as an exact fit the cylindrical end of a motor shaft; the motor and pump are connected together by a connection flange, the two shafts being obliged to rotate together by keys interposed between the coupled surfaces of the two shafts and inserted into appropriate recesses.
The aforestated thermal motor shafts cannot however be coupled to said reciprocating pumps. However, for of those firms which market these pumps it would be advantageous to be able to couple them to said thermal motors, both because these are widely available and because this extends in the facility for using such motors, examples of which are often held in stock.
An object of the present invention is therefore to make it possible to couple the shaft of said thermal motors to the shaft of said reciprocating pumps, using coupling means of small overall size and simple construction.
This and further objects are attained by the invention as characterised in the claims.
The invention is described in detail hereinafter with the aid of the accompanying figures which show one embodiment thereof by way of non-limiting example.